Thus, the restoration theory fails to consider these possible influences on sleep. This supports the view that sleep helps restore the body physically because the immune system consists of protein molecules which as regenerated during cell growth in SWS.
However, little other research provides the same conclusion.
For example a dolphin, which is very mature from birth, requires very little REM sleep whereas a platypus, which is very mentally immature from birth, has almost 8 hours of REM sleep. For example, Everson et al found that sleep deprivation in rats causes them to increase their metabolic rate.
Another weaknesses of restorative explanations of the function of sleep is through the support alternative theories have gained, which serves to challenge the restoration theory.
However, to explain the functions of sleep using only the restoration theory would be a reductionist account, because it fails to take in other explanations such as the evolutionary approach.
If the function of sleep was restoration of mind and body then surely we would all sleep the recommended 8 hours a day; however, some people are known to sleep just 2 hours, thus the theory fails to explain these differences.
However, if we view things from a behavioural perspective, it is likely to see sleep as a product of social norms. Furthermore, if we convince ourselves that we need 8 hours sleep and we only get 5, it is likely we will feel tired due to these expectations. To achieve REM sleep deprivation, researchers wake sleeping volunteers as soon as their eyes start to move.
Such sleep patterns may be related to the process of evolution because environmental pressures lead to differences in sleep patterns in different species.
When a rat was presented with a new environment and given a problem to solve, researchers found it slept for a longer period of time, suggesting that sleep is related to LTM, weakening restoration explanations as they fail to consider other functions which have achieved support.
Most studies thereby lack population validity because participants in sleep deprivation studies are likely to be of a certain personality type. Also, Sassin et al found that when people changed their sleeping patterns to sleep during the day and stay awake at night the levels of GH also changed.
Although these cases support restoration accounts, they are very rare and patients clearly have brain damage, making it difficult to generalise the findings.
They propose that sleep serves a restorative function. Rechstaffen et al forced rats to remain physically active by rotating a disk they were on every time they fell asleep.
Alternatively, REM sleep has been associated with brain growth. This suggests that the restoration theory is reductionist. Overall, there are issues with human research into sleep deprivation because the samples have been generally restricted to case studies or observational studies of small groups of participants.
The restoration explanation suggests that the amount of REM sleep in any species is proportional to the immaturity of the offspring at birth; for example the platypus is immature at birth and has about 8 hours of REM a day, whereas the dolphin can already sleep from birth and has no REM from birth.
Furthermore, Horne also points out that amino acids are only freely available for 5 hours after a meal and people usually sleep several hours before going to bed.
Short-wave sleep A strong link has been found between growth hormone GH and tissue repair. This second question is why some psychologists suggests there are other reasons for sleep, including environmental pressures. To test whether SWS has an important restorative effect, there have been studies undergoing sleep deprivation to see the effects on the body.
The restoration theory also places too much emphasis on the biological approach which views the function of sleep as something that is determined. For example, according to the brain plasticity theorists, sleep aids processes such as memory consolidation and learning.
Exercise and sleep — if the restoration theory is true we should also see an increased need for sleep, in particular SWS, as we look to restore the body after intense exercise. Studies have been carried out on non-humans which show that total sleep deprivation has fatal consequences.
And secondly, why do we need to fall unconscious to sleep? After 33 days, all sleep-deprived rats which suggests that a total lack of SWS after a while breaks down the body and kills a person.
Young supports the evolutionary account by suggesting the more we know about the sleep patterns of other species, the more it becomes apparent that environmental pressures rather than restoration provide the key to understanding sleep. Research has found that GH levels are steady throughout the day but then much higher at night.
Oswald said that short-wave sleep SWS is for restoring the body in terms of physical activity, whilst REM sleep is for resting the brain functions.
However, Breedlove et at found intense exercise may cause you to fall asleep more quickly, but it does not cause an increase in the duration of sleep. This suggests a relationship between neural development and REM sleep.Sleep is believed to function as a means of restoring the biological system to a better working order this is the basis of the restoration theory, Sleep is divided into several different stages such as SWS, and REM sleep, Oswald proposed that each of these sleep stages has a different restorative function.
Recently, researchers have uncovered new evidence supporting the repair and restoration theory, discovering that sleep allows the brain to perform "housekeeping" duties.
In an October issue of the journal Science, researchers published the results of a study indicating that the brain utilizes sleep to flush out waste toxins. The restoration theory makes the following predictions: During periods when the brain is growing or undergoing reorganisation, there will be an increase in the amount of REM sleep a person has.
May 22, · The restoration explanation suggests that the amount of REM sleep in any species is proportional to the immaturity of the offspring at birth; for example the platypus is immature at birth and has about 8 hours of REM a day, whereas the dolphin can already sleep from birth and has no REM from birth.
Psychology Essay Describe and evaluate one theory of the function of sleep (24 marks) Recovery/ Restoration is one theory on the functions of sleep. This theory is based on the concept that sleep is needed to save energy and to allow restoration of tissue.4/5.
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